[Greenbuilding] SIPs vs. fix/improve the roof/ceiling

[Chris Green]

Justin Close wrote:
> I have this odd little idea (or is it a dream?) about my current home.  
> I live in a 1955 stick built house with no insulation in the walls 
> (2x4).  <snip>
> My little idea is to remove the roof and replace it with structural 
> insulated panels (SIPs).  This would solidify and straighten out the 
> roof and provide needed insulation and sealing.  It would also allow for 
> less concern when installing lights in the existing ceiling (won't have 
> to penetrate the insulation layer).  Is this possible, practical, 
> sensible? 
>   
Assuming this is a simple peaked roof for a bungalow with one level, I 
think it is possible, since it has been done elsewhere by others.
Often after a roof has been torn off by winds.
With good planning, good site access for the lifting crane, and good 
general logistics, a skilled crew might be able to finish such a job in 
perhaps 5 to 8 days. Sunny, dry days, one hopes. {keep in mind I 
frequently underestimate the time a job should take...:-) ]
That's assuming it's a one story 1950's bungalow, where the roof looks 
like a folded sheet of paper, of course.
A roof with more than one level, angles, or other complications, makes 
it more of a challenge, but not impossible.

The SIPs will be thicker and probably weigh more than the old roof, so 
the new trusses will have to be professionally designed to transfer the 
weight onto existing load-bearing walls.

Once you start to change one thing, you'll have to upgrade a lot of 
other stuff.
Wiring, especially, plumbing, probably, venting from the heating system 
also probably, and more. The existing ceiling will probably have to go 
as well...Since you should brace the walls to keep them straight while 
the roof trusses are being replaced, this means most of the paneling 
inside will need to be replaced.
Which will likely have to be done anyways, to remove old wiring and 
install the new.
And so it goes.


Cheers, and Happy New Year,

Chris Green.